Detection of the XXY trisomy in a bull by using sex chromosome painting probes

Two cattle chromosome painting probes, identifying X and Y heterosomes, were applied to verify the diagnosis of XXY trisomy in an 8-month-old bull of the Polish Red breed. The probes were obtained after chromosome microdissection and labelled with biotin-16-dUTP. In all metaphase spreads, three fluorescence signals were observed - two X and one Y - confirming the diagnosis of a pure XXY trisomy.